﻿//======================================================================
//
//        Copyright (C) 苏州逸仙软件    
//        All rights reserved
//
//        filename : WebUpload.cs
//        description :
//
//        created by 周济 at 2010/12/21 17:25:19
//        mail:80406241@qq.com
//
//======================================================================
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.IO;

namespace huaguwang.swfupload
{
    public partial class WebUpload1 : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

            System.Drawing.Image thumbnail_image = null;
            System.Drawing.Image original_image = null;
            System.Drawing.Bitmap final_image = null;
            System.Drawing.Graphics graphic = null;
            MemoryStream ms = null;
            try
            {
                // Get the data
                HttpPostedFile jpeg_image_upload = Request.Files["Filedata"];

                string Filename = jpeg_image_upload.FileName;
                var FiletypeList = Filename.Split('.');
                var Filetype = "";
                try
                {
                    Filetype = FiletypeList.LastOrDefault().Exp_Trim();
                }
                catch(Exception)
                {
                    Response.StatusCode = 500;
                    Response.Write("An error occured");
                    Response.End();
                    return;
                }


                // Retrieve the uploaded image
                original_image = System.Drawing.Image.FromStream(jpeg_image_upload.InputStream);

                // Calculate the new width and height
                int width = original_image.Width;
                int height = original_image.Height;
                int target_width = 100;
                int target_height = 100;
                int new_width, new_height;

                float target_ratio = (float)target_width / (float)target_height;
                float image_ratio = (float)width / (float)height;

                if(target_ratio > image_ratio)
                {
                    new_height = target_height;
                    new_width = (int)Math.Floor(image_ratio * (float)target_height);
                }
                else
                {
                    new_height = (int)Math.Floor((float)target_width / image_ratio);
                    new_width = target_width;
                }

                new_width = new_width > target_width ? target_width : new_width;
                new_height = new_height > target_height ? target_height : new_height;


                // Create the thumbnail

                // Old way
                //thumbnail_image = original_image.GetThumbnailImage(new_width, new_height, null, System.IntPtr.Zero);
                // We don't have to create a Thumbnail since the DrawImage method will resize, but the GetThumbnailImage looks better
                // I've read about a problem with GetThumbnailImage. If a jpeg has an embedded thumbnail it will use and resize it which
                //  can result in a tiny 40x40 thumbnail being stretch up to our target size


                final_image = new System.Drawing.Bitmap(target_width, target_height);
                graphic = System.Drawing.Graphics.FromImage(final_image);
                graphic.FillRectangle(new System.Drawing.SolidBrush(System.Drawing.Color.Black), new System.Drawing.Rectangle(0, 0, target_width, target_height));
                int paste_x = (target_width - new_width) / 2;
                int paste_y = (target_height - new_height) / 2;
                graphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic; /* new way */
                //graphic.DrawImage(thumbnail_image, paste_x, paste_y, new_width, new_height);
                graphic.DrawImage(original_image, paste_x, paste_y, new_width, new_height);

                // Store the thumbnail in the session (Note: this is bad, it will take a lot of memory, but this is just a demo)
                ms = new MemoryStream();
                final_image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);

                // Store the data in my custom Thumbnail object
                string thumbnail_id = DateTime.Now.ToString("yyyyMMddHHmmssfff");
                Thumbnail thumb = new Thumbnail(thumbnail_id, Filetype, ms.GetBuffer(), jpeg_image_upload);

                // Put it all in the Session (initialize the session if necessary)			
                //List<Thumbnail> thumbnails = Session["file_info"] as List<Thumbnail>;
                //if(thumbnails == null)
                //{
                //    thumbnails = new List<Thumbnail>();
                //    Session["file_info"] = thumbnails;
                //}
                //thumbnails.Add(thumb);


                Session["file_info1"] = thumb;

                Response.StatusCode = 200;
                Response.Write(thumbnail_id);
            }
            catch
            {
                // If any kind of error occurs return a 500 Internal Server error
                Response.StatusCode = 500;
                Response.Write("An error occured");
                Response.End();
            }
            finally
            {
                // Clean up
                if(final_image != null) final_image.Dispose();
                if(graphic != null) graphic.Dispose();
                if(original_image != null) original_image.Dispose();
                if(thumbnail_image != null) thumbnail_image.Dispose();
                if(ms != null) ms.Close();
                Response.End();
            }

        }
    }
}